Tracking device.



A Patented Mar. 17,1914.

,2 SHEETS-SHEET 2.

y 'Ii W" JOSEPH I. HULDER, OF NEW YORK, N. Y.,

AssiGNoR To LUDWIG AND COMPANY, .A

CORPORATION F NEW YORK.

TRACKING nEvIcE.

Application led March 29, 1912.

specification of Letters Patent.

Patented Mar. 17, 1914.

serial No. 687,057.

To att 'w/iom it Wi ay conc-ern Be it known that I, JOSEPH P. I-IULDER, a citizen of the United States, and a resident of the city of New York, county and State of New York, have invented certain knew and useful Improvements in Tracking Del vices, of which the following is a full, clear,

. and exact specification.

My invention relates to a device for automatically maintaining accurate operative relation bet-Ween the note perforations in a traveling music sheet and: the corresponding apertures in a tracker bar.

c The principal object of this invention is to provide an automatic device which is self adjustable to and operable with note sheets of various width, be the same wider or narioiver than standard.

In operating an instrument provided with my improved l,tracking device, it'is merely necessary to insert the music roll in the customary manner, when, by reason of the construction and arrangement of parts ofthe device, it will adaptitself to the Width of the sheetand maint-ain the perforations thereof in" accurate registration With the tracker bar openings during the playing of the sheet, Without further attention by the operator.

'.sheet, normal relation will be restored.

A further advantage of my invention consists in providing means for'holding the edge guide out of'contact with the edge of the sheet during the re-rolling ofthe sheet, so as toV prevent-damaging the edge thereof. In the accompanyingdrawings illustrating' my invention Figure lis a rear elevation of my improved device. Fig. 2 is a plan viewpartly in section throughthe longitudinal vcenterline of the .tracker bar.

Fig. 3 is a frontd elevation ofthe tracker y showing the sheet guides Vand correlated parts. Fig. 4 is a section through the-valve -block. .Figp 5 is a front end View of the same. =I `ig`. 6 is a View of the inner :face

of the valve cap, and Fig. 7 is a view of the valve cap looking edgewise.

(1') Y designates a perforated note sheet which1 is arranged to be drawn over the These rolls are supported on longitudinally .movable spindles (5) which are mounted in the tracker box in the customary manner and are provided, at one end, with the usual thrust bearings (6) tendingto force the rolls from rightto left, as shown in Fig. 1.

(7) indicates a regulator pneumatic in which a partial vacuum is normally maintained by communication with the suitable exhaust chest (8).. A rod (9) connects the movable leaf of' said pneumatic with a pivoted @bar (10) having arms which abut against the left hand ends of the spindles -n'ote apertures in a tracker bar (2) from a ,carrying roll on to a take up roll V(4).

(5) so that upon decreasing the tension in y 'cates through a iexible tube (12) With a bypass (13) formed in the valve block (14'), and connecting With an exhaust prt (15), also formed in said block, the rear end-of which port communicates through a flexible tube (34) with the regulator pneumati (16) represents a laterally movable edge guide which is pivotally mounted as at (17) tothe rearwardly extending arm (18) carried on the tracker bar for contact With the edge of the sheet opposite to the guide opening (11). A rod (19)- connects the edge guide with the -valve cap (20), pivotally secured as at (21)*t0, the valve block (14). The'spring (22) acting against the valve (20) tends to press it inwardly so as to cause it to follow the movement of, the edge guide. Y

The valve block is provided' with an lexhaust channel (23) in addition to fthe above mentioned exhaust port (15) and by-pass (13). The rear end of this channel communicatesthrough a flexible connection (33) with the exhaust chest (8). The forward constituting the seatffor the valve cap` (20.)

i The valve cap is formed lwith a. groove serving as an lexhaust passage fo'r esvariable communication between tablishing the exhaust channel The upper arm (25) of this groove is made large enough to be in constant and Imrestricted communication with the exhaust channel, while the lower arm (26) is made opening (11) and disposed so that when the valve cap is swung outwardly it will gradu- Ially close'the port and viceversa, thereby controlling the area of said port so as to govern the exhaust of the ,regulator pneumatic upon -any deflection of the sheet. As the height of thev air intakey (11) is equalI 'to the height of the arm'(26) 1s adjusted so of the valve, the areas of the intake and exhaust openings will be a function ofjtheir length, or in other words, the'quantity .of air which is admitted to the regulatorzpneumatic through the opening (11) will depend relative position of upon and vary with the the edge of the sheet with ,regards to vsaid opening, while the quantity of'air that is exhausted from thev pneumatic will depend upon and vary with the areav of the opening of the port ('15) which area is governed by the movement ofthe valve cap following the lateral ymovement of the other :edge of the sheet.

The intake' (11) andthe edge guide (16) are spaced equally distant'from but on oppo'- site sides ,of the center of the tracker bar, and in setting up the device, the valve (20') that when the note sheet is in normal position, the area of the exhaust port` (15) will be lequal to the area of the intake. By referring to Fig. 3, it will bel seen that as the sheet shifts from right' to left,'the v intake (11,) -is gradually opened, while at the same time the exhaust portl (15) is being gradually closed in acorresponding'amount, and

vice versa. v

The valve block is preferably hinged as at (27) to the'side of the tracker box, and pro# vided witha set screwl (28) whereby it may be readily adjusted to bring the exhaust port (1'5) into correct initial position with respect to the arm (26). of the groove in the valve cap; Afterthe valve has been prop- In order to Withdraw erly adjusted, the device will operate Awith note sheets of various width without further adjustment. l

the edge guide from contact withthe ,edge of tliesheet during the 1re-rolling operation., I provide a pneumatic (29). which communicates Ywithtlnide guide. While the instrument isbeing played this pneumatic is collapsed, and consequently the string is slack, permitting free play of fthe edge guide to followthe'movement of the sheet, butv whilethesheet is ber- (23) and the port (1.5).

to the height of thei standard merely decreases 'into and tend to movable leaf of 4 direction a fixed music roll.

The operation of thedevice isdependent/@yg upon having an equal ratio between the; areas of the intake' (11) and the exhaiist'.V port`(15) when the note sheet is in ,normal position, and maintaining this ratio constantv during'thetravel of the sheet. The 75 width of on both 4sides of its central line. Thedifference in the width of they va-rious commercial note sheets is, however, comparatively slight. It Will lbe seen, therefore, that av sheetwhich is wider or narrower thanVJ or increases the extent of said areas without disturbing'the ratio between them, and that consequently, the device is self adjustable to sheets of va? Vrious width. f Y The mode of operation of my invention is as follows YV hen the sheet. is in normal relation to thenote openings in the tracker, the area ofthe intake opening (11)` will be equal to thewarea of the exhaust port( 1,5), and all i the air entering said opening willbe sucked through the by-pass (13.) into the exhaust chest. As, however, the sheet is deflected from its true path of travel, one edge thereof will tend to cover or uncover the opening (11),' depending upon-the direction'of the defiection, and the edge guide( (16)V with its connected valve (20) following lthemovementof the other edge of the sheet, will' tend to open or close the exhaust port (15) ina, corresponding amount. When, by reason of @the deflection of the sheet, the areaof the exhaust port becomes greater than the area. of the intake, the effective suction, tending to cause the regulator pneumatic to collapse, will be proportionate to the difference ofsaid areas, and similarly, when the area' lof the intakebecomes greater than the area of the exhaust port, a quantity ofair in prop1r' tion to the diffe ence of said vareas will enter expand the regulator pneu- Tle'c'onsequent movement of the the regulator pneumatic lwill' tend to cause the sheet to be shifted inA a' apposite tothe direction. of itsy de- Hection an' thereby restore normal'rlation. VIn the foregoing specification, I have def scribed thebest modein whichlhave aps lplicd the principle of vmy invention, but it wil that. the-principle thereof 'may Ylie. applied in oth; modesg-jas'fr" example, to shift `the p s rono'f a novable tracker witli respect of matic.

' What I claim'as invention is 1-. In combination, apneumatic having van exhaust port, a guide opening disposed under one edge of a note sheetand communi;

eating with the pneuinertia;v ain-edge guidem a note sheet 4is distributed equally iis be understoodby those skilled in the art,

sheet is properly tracking; a laterally movable edge guide contacting with the opposite edge of the sheet; a pneumatic communicating with'the guide opening and provided with an exhaust port; a valve operatively connected with the edge guide for controlling the effective cross Asectional area of the ex- 'haust port and equalizing it with theuncovered, area ofthe guide opening; ,and means-operated by the pneumatic for main taining pro er relation between note sheet andthe trac er. Y

3.111 combination with a traveling note sheet, and a tracker bar; aguide opening disposed in the path of andv partially covered by one edge of the sheet when traveling accurately; a laterally movable ed e Guide contacting with the other edge of t e sheet; and means `forrestoring normal relation between the tracker and the sheetV upon any deflection of the latter, said means being governed by means which include the guide opening and the edge guide.

4c. A tracking device for an instrument."

employing a traveling note sheet, lcomprising a guide opening, located under one edge of the note sheet andvpartially covered thereby when the sheet is properly tracking; a laterally movable edge guide contacting with the opposite edge of the sheet; a pneumatic communicating` with the guide opening and provided with an exhaust port; eX- I haust apparatus communicating with the exhaust Vport of said pneumatic; a valve operatively connected with the edge guide for controlling the exhaust port adapted to be moved by the shifting of the sheet to gradually open or close said port, said valve being adjusted so that when the sheet is 4in normal position the eiective cross sectional area of the exhaust port will be equal to the uncovered area of the guide opening,- and that -when the sheet shifts, the area of the exhaust port will be increased or decreased in inverse ratio to the decrease orincrease of the uncovered area of the guide opening, thereby varying the air tensionin the pneumatic; and means operative upon a variation of the air tension in the pneumatic to restore the sheet to normal position.

5. `In a tracking device the combination of lanv edge guide, an expanding spring for drawing and holding the edge guide away from the sheet, and a pneumatic for cornpressing lthe spring during the tracklng operation to permit the edge guide to contact with the edge of the sheet.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

JOSEPH P.' HULDER. Witnesses:

MICHAEL J. Owniirs, JosErH E. MCCUE.

copies of this patent may be obtained for uve cents each, by addressing the i Commissioner ot Patents, Washington; D. C. 

